The Elasticity of Time

Sorry about the delay since my last entry. I had a couple of things I wanted to say about cars that just really got away from me. I've decided to move on (and maybe finish them later).

What I've been thinking about today is a concept that I like to call the elasticity of time. I'm sure there is some other term for the phenomenon, but I am too lazy to look it up.

I'm referring to a concept that I am sure everyone has experienced: the feeling that time seems to pass faster and faster as we get older. If this phenomenon is not universal, then it must at least be widespread, for I've never encountered anyone who didn't know what I was talking about when I brought it up.

Here are my questions:
1. Is the elasticity of time universal?
2. If it is, is it experienced in a universal fashion?
3. If it is experienced in a universal fashion, what is the nature of that fashion?
4. How can this information be used to make our lives a little better?

1. I believe it is universal. If it is not, then it seems at the very least to be universal within our culture, which can still be highly relevant. I suppose the only way to know for certain would be to study people of vastly different cultures and see if they experience a similar acceleration in the perception of time passing.

2. What I mean by this is whether or not everyone experiences the phenomenon in roughly the same way. Does the difference of one year at 30 relative to one year at 20 feel about the same for you as it does for me? I realize that this is a fairly subjective thing, as we are talking about how long a period of time feels. But I would argue that you can still make a fairly objective assessment about how long time feels to large groups of people.

3. This is just a guess, but right now it's as good as any. I would hypothesize that the perception of the speed of a period of time is relative to the amount of memory that a person has over their lifetime. Meaning that the reason a year feels shorter when you are 20 than it did when you were 10 is because when you were 10, it represented 10% of your total lifespan, versus only 5% when you are 20.

4. How can this be used? This is where it gets interesting. Let's first take a look at life expectancy in the United States, it's 78.6 years. We'll call it 79. Now let's take a look at how long a year feels. Normally, I would discount the first few years of childhood as nobody has a working memory of being an infant and this whole thing is kind of dependent upon the memory of time, but for simplicity's sake, I'm just going to leave it in. From 0-1 a year is 100% of your life, from 1-2, 50%, from 2-3, 33%, and so on. like this

First year - 100%
Second year - 50%
...
Seventy Ninth year - 1.27%
Total - 495.3%

Well, this can't be right.

Using only that most simple of formulas speculating that each year feels differently relative to how much of your lifespan it represents means that an average lifespan would only subjectively feel like five times the length of the first year. Put another way, at 30 years old it means that one year should feel like only 0.67% of an entire life (3.33% / 495.3%). This would suggest that an actual lifespan would feel like 148 years to a 30 year old. Somehow, I doubt this to be correct.

Then what is the formula?

Maybe it's not that we're on the wrong track here. Maybe it's just that we're starting too early. As I said before, nobody remembers their first years. Even once memories do start to form, there's still a ton of development and craziness happening that makes all of that time a little tricky to factor in with all of the rest of the time I spend, you know, being human.

What happens if I start the clock when I first noticed how much quicker one year felt from the last. For me, it was probably right around adolescence. I'll start at 13. Like this

13th year - 7.69%
14th year - 7.14%
...
Seventy Ninth year - 1.27%
Total - 184.98%

Suddenly this looks a lot closer to how it actually feels. This means that a year to a 13 year old is over 4% of their subjective life expectancy (which helps explain why people over 30 seem so ancient to teenagers). This also means that a year at 30 is going to feel 50% faster than a year at age 20 and a year at age 40 is going to feel a full third faster than a year at 30. This isn't actually too unreasonable.

What actually got me thinking about all of this is how much I hate working. Say you graduate from college at 21 and enter into the workforce. Also say that you somehow manage to get one of these great careers that you will actually be able to retire from at 60. Now say that you're, I don't know, 34, and you just want to know subjectively how much time you have left. Now we have a formula for that:

x = (1/21 + 1/22 + 1/23.....1/n) divided by (1/21 + 1/22 + .... 1/60) wherein n is your age.

What I get is 48.09%. What this means is that even though I have only worked for one third of my estimated working life, it should feel like I am very nearly half way done given the subjective acceleration of time. In another year I will be full on half-way through the muck. Yippee.